Research Gist
This laboratory study examined how nanoparticle size affected the uptake of barbiturate-coated gold nanoparticles by cultured mouse brain endothelial cells used as an in-vitro blood–brain barrier model. Spherical nanoparticles measuring approximately 20, 50, 70 and 110 nm were compared under the same exposure conditions. The 70 nm particles produced the greatest total amount of gold inside or associated with the endothelial cells, while the 20 nm particles provided the greatest total available surface area. The results suggest that the preferred nanoparticle size may depend on whether an application requires maximum material uptake or maximum surface area for attaching therapeutic molecules. However, the experiment measured endothelial-cell uptake, not confirmed passage through an intact blood–brain barrier into brain tissue.
Key Learnings
- The researchers compared barbiturate-coated gold nanoparticles of 20, 50, 70 and 110 nm using cultured bEnd.3 mouse brain endothelial cells.
- The cells were exposed to equal amounts of gold for 30 minutes, and each size group was tested in triplicate.
- The 70 nm nanoparticles produced the highest gold uptake per cell, approximately 0.21 ± 0.03 ng per cell.
- The 20 nm nanoparticles provided the greatest total free surface area, which may be useful when therapeutic molecules are attached to the nanoparticle surface.
- Barbiturate-coated 20 nm particles showed considerably greater cellular uptake than the mPEG-coated control particles, although the control data were not displayed in the paper.
- Confocal imaging supported substantial nanoparticle internalization, but also indicated that some particles remained attached to the cell surface.
- This was an in-vitro endothelial-cell uptake study. It did not demonstrate transport into the brain in animals or humans, and it did not report a dedicated safety or cell-viability evaluation.
